The present invention relates generally to the field of devices for administering anesthesia, and more particularly to an improved mask apparatus for administering anesthesia to a patient.
Apparatus for the administration of anesthetic gas to a patient are known in the prior art. Generally, such apparatus are used by dentists for dispensing anesthetic gases such as oxygen and nitrous oxide to a patient during procedures in the dental office. Such systems generally include a source of the anesthetic gas, an apparatus to deliver the gas to the patient, and a scavenging system whereby the gas that the patient exhales is captured and is prevented from escaping into the room. A mask is fitted to the face of the patient and embraces and covers the nose and/or the mouth of the patient. Flexible tubing between the mask and both the source of the anesthetic gas and the aspirator is employed. Generally, such tubing is in the form of flexible hose. Examples of such apparatus are disclosed in U.S. Pat. Nos. 4,219,020, 4,015,598 and 5,018,519 and shown in FIGS. 3-6.
However, the prior art is problematic. The apparatus known in the prior art have a large number of components and high part count, which increases the costs of manufacturing and assembly. The high number of components also increases the chance of improper assembly when in use. Second, the prior art does not embrace the nose and mouth of a patient as symmetrically and closely as may be desired. Third, the scavenging masks known in the prior art do not fit properly over the head of the patient and are cumbersome because of the number of tubes employed in the delivery and exhaust of the subject gas.
Accordingly, it would be beneficial to have a gas delivery apparatus with an exhalation evacuator which has reduced part count, is balanced, embraces the patient""s face appropriately, allows for interchangeable sizes, and generally addresses the deficiencies in the prior art.
With parenthetical reference to the corresponding parts, portions or surfaces of the disclosed embodiment, merely for the purposes of illustration and not by way of limitation, the present invention provides an improved exhalation evacuator (15) having a mask (16) with an inhalation portion (18) and an exhalation portion (19), a delivery conduit (20) communicating with the mask, a return conduit (21) communicating with the mask, the delivery conduit having a supply end (22) and an inlet end (23), the inlet end having an inlet gas passageway (24) and a first connect port (25), the return conduit having an outlet end (26) and an exhaust end (28), the outlet end having an exhaust gas passageway (29) and a second connect port (30), the gas passageway of the delivery conduit communicating with the inhalation portion, the gas passageway of the return conduit communicating with the exhalation portion, the first connect port engaging the exhalation portion, the second connect port engaging the inhalation portion, the first and second connect ports not having a passageway allowing gas to move between the mask and the delivery and return conduits, respectively, the gas inlet passageway and first connect port having an inverse orientation and functionality with respect to the exhaust gas passageway and the second connect port.
The inlet end may have a Y-configuration. The supply end may have a first diameter (31) and the exhaust end may have a second diameter (32) and the first diameter and second diameter may be different diameters. The inlet gas passageway and the first connect port may be integrally molded or permanently affixed to the delivery conduit. The inlet gas passageway and the first connect port may be an integrally molded member detachable from the delivery conduit and the mask. The first connect port may comprise a first cylindrical inner surface (55) that defines a first recess (44) and the second connect port may comprise a second cylindrical inner surface (56) that defines a second recess (33). The second connect port may comprise a bridge member (34) adapted for engagement between the second inner surface and the inhalation portion.
Accordingly, the general object of the present invention is to provide an improved exhalation evacuator.
Another object is to provide an exhalation evacuator which allows for a reduced number of components.
Another object is to provide an exhalation evacuator which reduces the risk of improper assembly.
Another object is to provide an exhalation evacuator which has unique porting on the connecting pieces.
Another object is to provide an exhalation evacuator which is symmetrical and engages the face in a balanced manner.
Another object is to provide an exhalation evacuator which reduces the risk of interchanging the return scavenging tubing and the delivery tubing.
Another object is to provide an exhalation evacuator which reduces the amount of tubing to and from the mask.